Signs at the roadside are well known and extensively used to indicate speed limit, directions, potential hazards, the nature of the road ahead as to curves and conditions, and to indicate distances. They are also used to mount roadside reflective indicators.
It is common for such road signs to be supported on a cylindrical galvanised iron pipe which is buried in the ground at the side of the road. For more permanent attachments it is common for the supporting pipe to be embedded in concrete to avoid removal by vandals or accidental displacement in the course of time.
Such arrangements have a number of disadvantages. In particular because both the sign and the mounting arrangements are often damaged or destroyed upon impact by a vehicle, it is common for considerable effort of both labour and resources to be expended by local councils, authorities and the like in repairing damaged road signs. The repair work is also dangerous for the workers due to the proximity of road traffic. The substantially rigid nature of the connection frequently means that the support post for the sign has to be dug out and then repositioned. Alternatively it is necessary that the damaged sign be cut away from the mounting and a replacement sign welded in place.
Solidly mounted signs cause damage to vehicles as well as personal injury. Attempts have been made to overcome these effects by mounting the road signs on a spring so that upon impact the spring mounting enables the road sign to resiliently flex. It has also been proposed to minimise the damage to a vehicle impacting the roadsign by constructing the post supporting the roadsign from light gauge material. However such an arrangement still requires considerable time and effort to replace when destroyed.